This invention relates to a general service tungsten-halogen incandescent lamp, and more particularly, to a mounting arrangement for the inner envelope of the tungsten-halogen incandescent lamp which improves the shock resistance of an operating filament housed within the inner envelope.
Recent improvements to the incandescent art have provided a general service lamp having an inner envelope disposed within an outer envelope which contains a halogen compound, houses a tungsten filament and serves as a light source for the lamp. One such lamp is described in U.S. Pat. No. 4,647,809 of Blaisdell et al. issued 3/3/87.
The operating tungsten filament of the lamp is prone to hot shock type failures which may typically occur when a mechanical shock or impact of a sufficient amount is imparted to the outside of the lamp while the lamp is illuminating, causing the hot operating filament to oscillate a sufficient amount so as to possibly contact one of the two inner leads between which the filament is connected. If the oscillating filament does contact the related inner lead, then the filament is electrically shorted and fails. Due to the relatively close environment within the inner envelope a sufficient amount of spacing between the inner leads and the axially aligned operating filament cannot be provided so as to completely eliminate the possible occurrence of this hot shock problem. It is desired that an arrangement of a general service tungsten-halogen lamp for mounting the inner envelope which houses the filament be provided to reduce or even eliminate the hot shock problem associated with the hot operating filament. Alternately, it is desired that means be provided within structure of the inner envelope itself to solve the hot shock problem. Still further, it is desired that a combination of the mounting means and inner envelope means be provided to eliminate the hot shock problem.
Accordingly, one object of the present invention is to provide a general service tungsten-halogen incandescent lamp with a mounting arrangement or means which reduces or even eliminates hot shock filament failures.
It is another object of the present invention to provide an inner envelope for a general service tungsten-halogen lamp having means to correct for the hot shock filament failures.
It is further object of the present invention to provide a combination of a mounting means and means within an inner envelope to correct for the hot shock filament failures.